Comment 46 for bug 318325

I can add more details :

I confirm that in Karmic with the package xserver-xorg-video-radeon version 1:6.12.0-0ubuntu1 instead of the default package version, the suspend/resume cycle works fine using the following command:
$ sudo pm-suspend --quirk-vbestate-restore
The option --quirk-vbestate-restore is the only one which is important. Other options can be added but this is useless because it works the same way.

I tried many combinaison of options with the version 1:6.12.0 of the package on Lucid (using --force-all option to install it) but it doesn't fix the suspend/resume cycle.